Low-pressure steam-heater.



No.705,98l. Patented July 29, 1902.-

F. TUDOR.

LOW PRESSURE STEAM HEATER.

(Application filed June 13, 1901.)

(No Model.)

WIT 55555:

UNITED STATES f PATENT OFFICE;

FREDERIC TUDOR, OF BROOKLINE, MASSACHUSETTS.

LOW-PRESSURE STEAM-HEATER.

SPECIFICATION forming part Of Letters Patent No. 705,981, dated July 29, 1902.

Application filed June 13,1901- Serial No. 64,484. (No model.)

To all whont it nuty concern.-

Be it known that I, FREDERIC TUDOR, a citizen of the United States, residing at Brookline, in the county of Norfolk and State of Massachusetts, have invented a new'and useful Improvement in Low- Pressure SteamlIeaters, of which the following is a specification.

Myinvention relates to low-pressure steamheating systems of the open circulation trapped-return class and is so contrived as to place in the hands of unskilled persons a valve apparatus which will enable them to control the steamheaters in such a way as to obtain heat in any quantity within the limits of their reasonable economy and will permit a hasty adjustment of the steam heating devices without attention to many details.

In my United States Letters Patent No. 318,401, May 19, 1885, I showed an arrangement whereby the common defect of heat in excess, the chief objection to steam-heating systems, was avoided by providing each ra-- diator in a low-pressure system with a throttle or constricted steaminlet, which was so proportioned that under normal conditions the throttle delivered to the radiator no more than the quantity of steam which that radiator could condense. This arrangement prevented the supply of more than a true maximum amount of steamthat is to say, an amount beyond the condensing capacity of the radiator When'in full action-and consequently guarded against the rise of back pressure in the returns and the accumulation of water in other radiators of the system through its action when the latter or any of them were shut off from the steam-supply and were supplied with less than the normal quantity of steam. This improvement was limited in the scope of its utility, for the reason that no devices were then provided whereby the heat delivery of the radiatorcould be reduced with certainty below the point of maximum condensing capacity. In my Patent No. 319,939, June 9, 1885, I showed an improved valve which supplied the place of the constricted throats of my Patent No. 318,401 and at the same time placed in the hands of the person using a radiator an instrument by which he might accurately and instantly grade the heat de livery of the radiator up to the point of de livery of the maximum condensable quantity of steam; but the valves of this Patent No. 319,939 were contrived to act only up to that maximum point and could not do more than that. The valve of Patent No. 319,939 is well adapted to supply and regulate the radiator under normal conditions. Its construction is such that an uninstructed or inattentive person cannot supply steam to the radiator in excessive quantity and bring on the unpleasant consequences of such excess in a reversed circulation and back pressure,causing noises and accumulation of water, and if normal external conditions were constantly maintained the valve of Patent No. 319,939 would serve every purpose; but these normal external conditions are by no means constantly maintained. When the occupant of a room has closed the radiator-valve and the roombecomes cold during the night, in the morning it is desired to warm it rapidly. This cannot bedone by means of the valves shown in Patent No. 319,939, because, the pressure of the steam being normally low and the maximum valve-opening being proportioned so as to discharge only a limited and fixed weight of steam in a given ti me-for instance, that maximum quantity which the radiator can condense when heated throughout and in an atmosphere at about 70 Fahrenheitthis opening is insutficient to deliver enough steam to warm the radiator and the room quickly under unusual conditions-as, for example, when the temperature is 'at 50 Fahrenheit. The shortage of steam is due to the fact that the radiator is cold and itself takes up the latent heat of most of the steam admitted to it for some time, during'which the room to be heated receives little or no benefit. The steam condensed in heating up the radiator itself before the surrounding air can be affected is relatively a large quantitycompared with the normal condensing rate. For example, a cast-iron radiator having about fifty square feet of condensing-surface Weighs about three hundred and fifty pounds. If the radiator is at 60 Fahrenheit, in order to warm it to 212 Fahrenheit there is required the condensation of about seven pounds of steam. The maximum condensing capacity of such radiator under normal conditions is about twelve and onehalf pounds of steam per hour, and the valve,

if like one of those shown in Patent No. 319,939, is adjusted to discharge this quantity asitsmaximum. Therefore tlietimerequired to warm the radiator to 212 Fahrenheit, regardless of its loss of heat by radiation during the process, will be thirty-five minutes. In practice the loss of heat from the radiator causes this period to extend indefinitely beyond an hour. Thus it is obvious that after steam has been shut off this delay in restoring comfortable conditions is a great disadvantage. It is quite clear that in the hands of an intelligent and careful person this disadvantage could be overcome by having an ordinary valve in a passover-pipe, so that the ordinary valve could be opened sufficiently to warm up the radiator quickly and could then be shut oif entirely, having the throttle-valve to perform its normal offices; but this involves putting an ordinary valve into the hand of an ordinary person, and this is what I Wish to avoid. Nine out of ten men in spite of printed directions to the contrary will merely open both valves of such a twovalve system and leave them open, sacrificing all the advantage of the throttling system; but if only one valve is provided and the occupant of a room has only to manipulate one valve-handle he soon gets accustomed to using that one valve, and if, as in the valves of Patent No. 319,939, there are visible graduations to show the position of the valvehandle he will govern his valve accordingly, throttling the steam when the room is too hot.

It is therefore the object of my present invention to provide a radiator in a steamheating system with a single admission-valve which will perform the functions of a graduated valve adjusted to the maximum condensing capacity under normal conditions and will also be capable of use as an emergency-valve, which delivers a larger quantity of steam than the maximum condensible qu antity'under normal conditions, which will present no diflicnlties or complications to the most untaught person, and which, in fact,cannot be made to go wrong.

The operating-handle of my improved valve is confined within the limits of a single revolution for its operative movement. Thus the danger of confusion or error due to the handle passing through the same path twice is avoided, and the position of the valve-ham dle always is an index of the exact position of the valve, which is not the case with ordinary valves,wherein the valve-handle may be turned more than once while the valve is being opened.

In the drawingshereto annexed there is ing my invention. Fig. 3 shows in plan the index dial or flange employed with my valve, and Fig. 4 shows a development of a cam which constitutes one of the operating parts in that embodiment of my invention illustrated in Figs. 2 and 3.

In Fig. 1 there is shown a radiator R, connected with the steam-riser pipe A and returnpipe B. These pipes are connected with the boiler in the usual way. At 1; the steam-regulating valve is located, and at T there may be placed a steam-trap or return-pipe protected against back pressure by a water seal or by a check-valve and water seal such as is described in Letters Patent No. 291,818, issued to me January 8, 1884. The valve placed at t operates according to the principles of construction embodied in the valve shown in detail in Figs. 2, 3, and 4.

Referring to Fig. 2, a valve-body G is provided with an inlet at r, from which steam is taken from the riser-pipe, and an outlet at 0", which leads to the radiator. The passage between the openings 1' and 1" is controlled by the valve V, which is urged toward its seat V by the spring S, this spring being of sufficient strength to overcome any ordinary pressure in the riser-pipe. The valve V is mounted on a cylindrical stem V which passes through the packing-gland 0 which forms part of the screw-cap 0. Upon the outer end of the stem V a handle H is secured by means of the screw-hub h and set-screw h Upon the top of the valve-body there is secured the stationary cam K, which is preferably to be formed in one piece with the flange F. The cam K cooperates with a cam-follower 7a, which is secured to or integral with the arm of the handle H. To this cam K, as shown at its development in Fig. 4, the handle is adjusted with relation to the valve-stem V so that when the valve is seated on the valve-seat V the cam-follower 7c rests at that point on the cam indicated by the zero-mark in Fig. 4. Thus as the handle H is turned in the direction of the rise of the cam it causes the valve-stem to be raised as it is turned and the valve V to be started from its seat. The valve-opening and the pitch of the cam K are so proportioned with relation to the radiator which is equipped with the valve that within the limits of a single revolution of the valve-handle and before the valve-handle has made its maximum excursion the valve V will be opened just far enough to admit to the radiator the maximum quantity of steam which it is to condense under nomal conditions. Between this point in the travel of the valve-handle and the zeropoint, which corresponds to the position of valve-closure, the heating capacity of the radiator under normal conditions may be regulated, and under normal conditions the traverse of the valve-handle will be limited to a range of movement between zero and the point of complete condensation opening. This valve is, however, so constructed that the point of complete condensation under normal condition is short of the full possible exour sion of the valve-handle, and the devices by which the valve is raised from its seat are so contrived that further movement of the valve beyond the point where maximum condensation occurs under normal conditions is accompanied by an opening of the valve and the passage controlled thereby which is capable of delivering steam in quantity far in excess of that which the radiator will condense under normal conditions, and at the same time the valve and its operative parts are so arranged that the complete valve-opening movement of the handle will not exceed a single revolution. In the valve shown in the figures these desired results are obtained by forming the cam K with uniform pitch from the zeropoint to the point of maximum condensation under normal conditions and with increased pitch beyond the latter point, so that while for all movements of the valve which effect intermediate graduation the valve-opening may be directly proportionate to the angular movements of the valve-handle the ratio is changed after the point of maximum condensation under normal condition is passed, and the valve handle and stem are lifted more abruptlybythecam-follower. Bythismeans a large portion of the cam-surface may be devoted to purposes of graduation and only a small residue be required for maximum or emergency opening. The valve-handle and .cam-follower may be provided with stops which positively limit its movement to a single revolution or less, or, as in the illustration shown, the high part of the cam, which corresponds to the largest opening of the valve, maybe approached from either direction from the zero-point. By employing this device the valve-handle can be turned freely in either direction, and there is no danger that a person previously unacquainted with the pur-' poses and construction of the valve will find any difficulty in setting it to produce a desired result.

The dial-flange F is shown in plan in Fig. 3 inits relation to the cam K. Opposite the point marked Shut is located the zero-point. On the cam K (see Fig. 4) the points marked, respectively, fi 35- indicate those points on the cam to which the cam-follower 70 must be moved to obtain throttle-openings of the valve up to the point of maximum condensation under normal conditions, which is, say, in this the point marked it, and for all ordinary conditions the valve-handle will be moved between the point marked Shut and the point marked it; but if for any reason the radiator becomes chilled and it is desired to Warm the room rapidly the valvehandle is turned until the pointer it rests over the Word Open, which stands opposite the highest point 10 of the cam K, and the valve consequently admits a quantity of steam to heat up the radiator by condensation in a very short time and maybe left in that position indefinitely, especially in very cold weather, when the greater intensity of heat due to a pressure of steam above that of the atmosphere may be availed of. After the room has become warm, to check the heat the person operating the valve has only to move the handle toward the point marked Shut as he feels the necessity for doing so.

The advantage of forming the cam K and index-flange F in substantially one and the same piece is obvious, because then no matter what the angular position of the flange and cam-piece when placed upon the valvecasing the position of the pointer h and the valve can be determined at once with reference to the cam by noting the graduationmarks upon the index-flange, and the valve can be fitted to any size or capacity of radiator within certain limits or in case of error more exactly fitted to its radiator by merely substituting another cam and index,without even shutting oif steam from the boiler.

The spring and cam controlled valve is effective in this respect: All wear or backlash is automatically taken up and the accuracy of the valve preserved. This is exceptionally important,because with a half-inch valveopening all the steam condensable by an ordinary radiator will be admitted through a valve-opening one one-hundredth (fi of an inch wide. If wear were permitted to detract from the accuracy of the valve, its graduating capacity would soon be destroyed.

The above-described valve and the subjectmatter which it illustrates is reserved for claim in another application.

What I claim, and desire to secure by Lettcrs Patent, isv 1. In a steam-heating system of the class indicated, the combination of a radiator, steanv supply pipe, a steam-valve controlling the admission of steam to the radiator, a returnpipe and connections therewith to the radiator, a manipulating-handle and associated actuating devices for the steam-valve having an opening movement which is limited within one revolution of the valve-handle, the valve mit to the radiator its maximum normal condensable quantity of steam before it reaches 1 the limit of its opening movement, and constructed to indicate the arrival of the valve at the said point of maximum normally condensable steam delivery.

2. In a steam-heating system of the class indicated, the combination of a radiator, steamsupply pipe, a steam-valve controlling the admission of steam to the radiator, a returnpipe and connections therewith to the radiator, a manipulating-handle and associated actuating devices for the steam-valve having an opening movement which is limited within one revolution of the valve handle, the valve and its actuating devices proportioned to admit to the radiator its maximum normal condensable quantity of steam before it reaches the limit of its opening movement,

constructed to indicate the arrival of the valve at the said point of maximum normally condensable steam delivery, and to accelerate the final opening movement of the valve with relation to the rate of angular movement of the valve-handle.

3. In a steam-heating system of the classindicated, the combination of a radiator, a steam -valve controlling the admission of steam to the radiator, return connections, a valve-stem, a cam surrounding the valvestem, a cam-follower secured to the stem, the said cam being so proportioned that a fraction of a full rotation of the follower suffices to open the valve to the point where it admits the normal maximum quantity of steam condensable by the radiator, and an indexscale for the cam-follower which marks the point of said normal opening; the full movement of the valve being limited to one revolution of the cam-follower.

4. In asteam-heating system of the class indicated, the combination of a radiator, a

the valve being limited to one revolution of the cam-follower, and the portion of the cam beyond the point of normal'maximum condensable steam delivery being of greater pitch than the initial-opening portion.

Signed by me at Boston, Massachusetts, this 8th day of June, 1901.

FREDEaIo TUDOR.

Witnesses:

E. T. GRoLL, FRANK S. HARTNETT. 

